Claude Opus 5.5 (High) vs DeepSeek-V4.1-Flash-20261017 (Max) Benchmark Comparison

Direct benchmark comparison between Claude Opus 5.5 (High) and DeepSeek-V4.1-Flash-20261017 (Max) based on LMArena Elo and the latest 2026 API pricing.

Direct Technical & Pricing Comparison

Frontier Model	LMArena Elo	API Cost (1M)	Throughput
Claude Opus 5.5 (High)	1508	$0.000004	73
DeepSeek-V4.1-Flash-20261017 (Max)	1670	$3e-7	215

*These models represent the Pareto Frontier (optimal cost-to-performance).*

Comparison Summary: DeepSeek-V4.1-Flash-20261017 (Max) is the more capable model in this pair, leading by 162 Elo points. Specifically, DeepSeek-V4.1-Flash-20261017 (Max) is currently on the Pareto line, suggesting it offers better systemic value for its performance tier.